Calendar of Physics Talks Vienna

Quantum mechanics has proven a remarkable theory for describing the
microscopic world. When combined with statistical assumptions, the
resulting thermodynamical theory provides the basis for much of our
classical understanding of the world. However, recent advances in
building devices that are well isolated have led to the possibility to
explore a wider range of phase space than statistical mechanics
assumes. I will discuss progress in building such quantum devices, and
their application in subjects from measurement science and
communication to quantum information processing.

Complex oxides have attracted great interest since they exhibit a rich spectrum of physical properties such as ferromagnetism, antiferromagnetism, colossal magnetoresistance, ferroelectricity, dielectricity, and superconductivity. Novel heteroepitaxial devices based on these complex oxides, like spin-polarized ferromagnetic tunnel junctions, superconducting devices and piezoelectric devices, have great potential and are currently under investigation in many groups.
The nature of the above-mentioned physical properties in complex oxides is determined by very small characteristic length scales, comparable to the unit cell lattice parameters of complex oxide. Because of these small characteristic length scales, growth control on an atomic level as well as understanding of the different mechanisms affecting the growth mode is essential for the fabrication of epitaxial heterostructures.
Two independent processes, i.e., nucleation and growth of islands, play an important role during vapor-phase epitaxial growth on an atomically flat surface. Here, nucleation causes the formation of surface steps and subsequent growth causes the lateral movement of these steps. Both processes are determined by kinetics, since they take place far from thermodynamic equilibrium. These kinetic processes affect the final surface morphology and are, therefore, extensively studied.
In this contribution, I will demonstrate the applicability of high-pressure RHEED as well as Scanning Force Microscopy (SFM) to monitor to the growth of complex oxides during Pulsed Laser Deposition (PLD). Furthermore, I will show recent examples, in which atomically controlled growth enabled new functionalities in complex oxide heterostructures.

These lectures are intended to be of practical help in explaining statistical ideas and techniques that are relevant for analyzing experimental data. The level is such that they should be readily accessible to graduate students who have had at least a little experience in analyzing experimental data, but especially from lecture 2 onwards, they should be of interest to post-docs as well. Some of the introduction is a speedy reminder of topics which should be familiar from undergraduate courses.
1) INTRODUCTORY TOPICS:
Probability and statistics; Binomial, Poisson, 1-D and 2-D Gaussian.
2) LEARNING TO LOVE THE ERROR MATRIX:
error matrix, covariance, correlated measurements.
3) PARAMETER DETERMINATION BY LIKELIHOOD: DO's and DONT's:
Error estimate; examples; misconceptions.
4) CHI-SQUARED and GOODNESS OF FIT:
Error estimates; kinematic fits.
5) DISCOVERY and p-VALUES:
Distinguishing a peak, a goof, and a statistical fluctuation; simultaneous optimization for discovery and exclusion; incorporating systematic effects.
TERMINE
Mittwoch 18. Mai 17:00-18:15 Uhr s.t.
Donnerstag 19. Mai 11:00-12:15 Uhr s.t.
Dienstag 24. Mai 16:00-17:15 Uhr s.t.
17:15-17:45 Uhr Kaffee und Kuchen
17:00-18:15 Uhr s.t.
Prof. L. Lyons is a leading authority on statistical analysis of data, having published several books on this topic. His ‘Practical guide to data analysis for physical science students’ is an international best-seller. Well known and appreciated for his didactic talents to turn a terse subject into an engaging topic, he has educated a generation of nuclear and particle physicists on the proper statistical treatment of measurements.